<%@page contentType="text/html;charset=utf-8" %>

<%
  pageContext.setAttribute("data","pageContext");
  request.setAttribute("data","request");
  session.setAttribute("data","session");
  application.setAttribute("data","application");
%>

<%--el表达式优先从小的域取数据--%>
<%--pageContext<request<session<application --%>
${data}<br/>

<%-- 在el表达式可以指定范围取数据--%>
<%-- el表达式有4个隐含的隐式对象--%>
<%--pageScope<requestScope<sessionScope<applicationScope --%>
${pageScope.data}<br/>
${requestScope.data}<br/>
${sessionScope.data}<br/>
${applicationScope.data}<br/>
